1. Technical Field
The present invention relates to a fluid ejecting apparatus, a method of maintaining the fluid ejecting apparatus, and a method of driving a tube pump.
2. Related Art
As a liquid ejecting apparatus ejecting liquid, for example, an ink jet printing apparatus, which prints characters and images on a printing medium, and the like are known. The ink jet printing apparatus ejects ink from nozzles provided in an ejection head onto a printing medium while transporting the printing medium, to form characters or images on the printing medium. The ink jet printing apparatus is provided with a cap covering an ejection area of the ejection head.
In the ink jet printing apparatus, clogging may occur on the nozzles of the ejection head by thickening or solidification of ink, attachment of dust, mixing of bubbles, and the like, thereby causing a fault in printing. When ink is initially charged in the ejection head, it is necessary to discharge liquid in the head from the nozzles. For this reason, a maintenance operation such as a cleaning operation of compulsorily discharging the liquid in the nozzles is performed separately from the ejection onto the printing medium.
In the cleaning operation, the liquid discharged from the ejection head is received using a liquid receiving portion such as a cap portion. The cap portion is provided with, for example, an outlet for allowing the received ink to flow out. The outlet is connected to an absorption mechanism such as a tube pump.
The tube pump has a tube member connected to the cap portion and having a curved portion with flexibility, and a roller member rolling in an inner circumference of the curved portion while pressing and deforming the tube member, and pressure of a space at the cap portion is changed by the rolling of the roller member.
The tube pump has a configuration in which the amount of absorption is changed by a starting position of the roller member. Particularly, when including a leak portion in which the amount of deformation caused by the pressing of the roller member is insufficient and a set value of the amount of absorption (rotation) is small, the starting position of the roller member is changed to cause non-uniformity in the actual amount of absorption, which is a problem.
For example, a tube pump described in JP-A-2009-51226 detects a phase of a rolling operation of the roller member using phase detecting means to stop the roller member at a predetermined position on the basis of the detection result. Accordingly, it is possible to suppress the non-uniformity in the amount of absorption for each cleaning operation.
However, in the technique of JP-A-2009-51226, it is necessary to separately provide the phase detection means, and thus there is a problem that the configuration of the tube pump is slightly complex.